SCIENTIFIC SUMMARY. 
193 
The Planets. — Saturn will be tbe only planet favourably situated for 
observation during- tbe coming quarter. His ring is now open to its widest 
extent. But tbe planet will be low when on tbe meridian. 
BOTANY. 
The Professorship of Botany in the Irish College of Science. — Tbis cbair bas 
been filled by tbe election of Professor Dyer, late of tbe Royal Agricultural 
College, Cirencester. Tbe choice of Mr. Dyer gave rise to great dissatisfac- 
tion among Irish scientific men, it having been thought that either Professor 
Perceval Wright, who bad especial claims, or Dr. M‘Nab, tbe eminent 
vegetable histologist, should have been preferred to tbe Cirencester Pro- 
fessor. However, now that tbe matter is decided beyond dispute, we have 
no doubt that Mr. Dyer will discharge bis duty with ability and distinction 
Mr. Dyer bas already done some good work in botany. Tbe appointment 
to tbe Dublin College leaves bis cbair at Cirencester to Dr. M‘Nab. 
The Geographical Distribution of the Conferee. — Mr. Robert Brown has 
sent us a reprint of bis valuable paper on tbis subject, published in tbe 
Transactions of the Botanical Society of Edinburgh. We have not space 
for all tbe author’s conclusions, some of which are of especial interest. In 
regard to tbe influence of temperature on tbe distribution of Conferee , be 
thinks that tbis is not so important as moisture, which latter, he thinks, the 
all-important element in tbe growth of forests,- tbe great steppes of Asia 
and prairies of America being almost entirely due to tbe absence of sufficient 
moisture for tbe prosperity of trees. Trees require at least from 15 to 16 in. 
of rain during tbe growing season. Tbe dense forests, for instance, of tbe 
western slope of tbe Cascades are wholly due to tbe abundant supply of rain 
that region obtains. Its effect is well seen in tbe treeless aspect of San 
Diego, in Southern California, which bas an annual rainfall of only 8| in., 
while Sitka, in tbe territory of Alaska, is deluged under tbe enormous rain- 
fall of nearly 7b feet per annum ! 
Heather a Productive Plant. — One would hardly think tbe growth of 
heather could be made commercially profitable, and yet M. Dromard, who 
writes on tbe subject in tbe Annales du Genie Civil of February, is of this 
opinion. In France, and in a great many other European countries, very 
large tracts of land are uncultivated and left waste, producing nothing but 
heather and similar plants. Tbe author’s lengthy memoir describes prac- 
tical methods whereby these plants are employed for the production of 
charcoal, acetic acid, tar, and other useful products, and the soil so cleared 
as to become fit for the cultivation of various kinds of fir-trees. 
Cinchona Groivth in India. — At the meeting of the Linnsean Society, on 
the 3rd of March, Mr. J. E. Howard read a paper by Mr. Broughton, 
chemist to the cinchona plantations in the Madras Presidency, “ On 
the Hybridisation among Cinchonas.” He believes that the sub-varieties 
of Cinchona officinalis are permanent, but that hybrids can be artificially 
obtained, although they do not occur in nature. The cinchona has long 
been known to belong to the class of dimorphic plants. In the discussion 
VOL. IX. — NO. XXXV. 0 
